I did many bad things in my life growing up and then got very sick. I just knew this was in part from my past behaviors. I repented in my heart and made every effort to stop my behaviors. My habits starting to change and I started to grow again and get well. During all of this I never confessed my sins to another. But I did get well again and eventually I even forgot about them. Then during a moment I confessed one of my sins to someone and it now comes back to haunt me. Better to let these things fade with time then to throw salt on a wound I say.
So In answer to your question - Become pure. Purify yourself. Change your thoughts, change habits, change your attitudes and then the rest will heal. It's slow going but eventually you'll get there. And I agree to confess would be needlessly cruel.
Also a broad way of dealing with your guilt. You could go to your family members and just tell them you want to make everything right with them. Tell them you want to heal all past hurts and disagreements and that you should all try to live more postively and more lovingly. That way you are in a way addressing the issue at hand indirectly but at least acknowledging the room for family growth. I did that and it helped a lot.